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Variation in chromium excretion in suckled cows at pasture
Published online by Cambridge University Press: 02 September 2010
Abstract
The diurnal cycle of chromium excretion was estimated over the last 24 h of a 13-day period in which nine single- and nine double-suckled cows were dosed twice daily (10.00 and 16.00 h) with shredded Cr2O3 paper. All faecal passages voided were sampled and analysed for chromium. Rectal samples were also taken at 10.00 and 16.00 h during this period. Sources of variation in the patterns of excretion that could be attributed to cow live weight, daily milk yield or total weight of the calf or calves being reared were also investigated.
Mean faecal Cr concentrations followed a cyclic pattern which was significantly described by a sinusoidal equation.
The estimated fundamental period (0·1334 rad/h) did not differ significantly from the theoretical value (2π/48 = 0·1309 rad/h). Fitting the model for each cow explained from 0·61 to 0·99 of the variation in faecal Cr concentration. Differences between suckling treatments in predicted faecal Cr content at discrete 2-h intervals over the 24-h period were not significant. Equations for heavier cows had lower constant terms, consistent with lower faecal Cr contents expected as a consequence of higher intakes. Differences in cow milk production and total calf live weight being reared were related to the pattern of Cr excretion (P < 0·05) but the reasons for these effects were not readily apparent. Mean Cr concentration in rectal samples was significantly correlated (r = 0·916) with mean 24-h faecal Cr content predicted from the model.
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- Copyright © British Society of Animal Science 1984
References
REFERENCES
Byrne, E. 1979. Chemical Analysis of Agricultural Materials. An Foras Taluntais, Dublin.Google Scholar
Corbett, J. L., Greenhaigh, J. F. D. and MacDonald, A. P. 1958. Paper as a carrier of chromium sesquioxide. Nature, Lond. 182: 1014–1016.CrossRefGoogle Scholar
Corbett, J. L., Greenhalgh, J. F. D., McDonald, I. and Florence, E. 1960. Excretion of chromium sesquioxide administered as a component of paper to sheep. Br. J. Nutr. 14: 289–299.CrossRefGoogle Scholar
Hardispn, W. A. and Reid, J. T. 1953. Use of indicators in the measurement of the dry matter intake of grazing animals. J. Nutr. 51: 35–52.CrossRefGoogle Scholar
Hopper, J. T., Holloway, J. W. and Butts, W. T. Jr 1978. Animal variation in chromium sesquioxide excretion patterns of grazing cows. J. Anim. Sci. 46: 1096–1102.CrossRefGoogle Scholar
Kane, E. A., Jacobson, W. C. and Moore, L. A. 1952. Diurnal variation in the excretion of chromium oxide and lignin. J. Nutr. 47: 263–273.CrossRefGoogle ScholarPubMed
Kotb, A. R. and Luckey, T. D. 1972. Markers in nutrition. Nutr. Abstr. and Rev. 42: 813–845.Google ScholarPubMed
Langlands, J. P. 1975. Techniques for estimating nutrient intake and its utilization by the grazing ruminant. In: Digestion and Metabolism in the Ruminant (ed. McDonald, I. W. and Warner, A. C.), Proceedings of the 4th International Symposium on Ruminant Physiology, Sydney, Australia, 1974, pp. 320–332. University of New England Publishing Unit, Armidale, Australia.Google Scholar
McIntyre, G. A. 1952. A method for unbiased selective sampling, using ranked sets. Aust. J. agric. Res. 3: 385–390.CrossRefGoogle Scholar
Nicoll, G. B. 1980. Evaluation of the machine washing of herbage samples cut at two heights. Ir. J. agric. Res. 19: 91–97.Google Scholar
Nicoll, G. B. 1982. Effects of double suckling at pasture. 1. Cow performance. Anim. Prod. 35: 385–393.Google Scholar
O'Shea, J. and Wilson, R. K. 1965. Relationship between in vitro and in vivo dry matter digestibility. Ir. J. agric. Res. 4: 235–237.Google Scholar
Raymond, W. F. and Minson, D. J. 1955. The use of chromic oxide for estimating the faecal production of grazing animals. J. Br. Grassld Soc. 9: 119–130.CrossRefGoogle Scholar